Reshape Pandas dataframe with DatetimeIndex to make grid

I have a pandas dataframe with a DatetimeIndex, e.g.

In: ts = pd.date_range('2013-01-01 00:00', periods=17520, freq='30min')
In: values = list(range(1, 17520))
In: df = pd.DataFrame(values, index=ts)

I want to reshape the dataframe so it has dates as the index and hours [0,0.5,1.0,1.5,.....] as the columns.

I have this:

df.pivot(index=df.index.date, columns=df.index.time, values='values')

but it gives me a key error with a list of dates not in index